Novel Stimulation Patterns for the Treatment of Dystonia

Summary

Deep brain stimulation (DBS) is an effective surgical therapy for select Dystonia patients who are refractory to medications or who have generalized symptoms (e.g. patients with Early-Onset Primary Dystonia(DYT1) mutations and other dystonia subtypes). DBS patients typically experience significant improvement in disabling symptoms; however, detailed programming is always required, and stimulation-induced side effects commonly emerge. Clinicians may empirically vary voltage, pulse width, frequency and also the active contacts on the DBS lead to achieve observed optimal benefits.

The majority of DBS patients undergo repeat surgeries to replace the implantable pulse generator (IPG) every 2.5 to 5 years. It has been demonstrated that, in dystonia patients, that higher settings are required for adequate symptomatic control, and that neurostimulators have a considerably shorter life when compared to neurostimulators from patients with essential tremor or Parkinson's disease. Additionally, several smaller studies have suggested that alternative pulse stimulation properties and pulse shape modifications can lower IPG battery consumption.

Newer patterns of stimulation (regularity of pulses and shapes of pulses) have not been widely tested in clinical practice, and are not part of the current FDA device labeling. Novel patterns of stimulation do however, have the potential to improve symptoms, reduce side effects, and to preserve the neurostimulator life.

The current research proposal will prospectively study biphasic pulse stimulation paradigms and its effects on dystonic symptoms. The investigators aim to demonstrate that we can tailor DBS settings to address dystonia symptoms, improve the safety profile, characterize distinct clinical advantages, and carefully document the safety and neurostimulator battery consumption profile for biphasic stimulation.

Conditions

• Dystonia
• Cervical Dystonia

Interventions

DEVICE

Biphasic DBS stimulation

The following protocol will be followed for each subject. In between, baseline and novel stimulation settings there will be a 30-minute washout period with DBS in the off state. 1. Current best/optimized DBS setting (considered "baseline") 2. DBS off for 30 minutes 3. Biphasic pulse stimulation mode (immediate assessment) 4. Biphasic pulse stimulation mode (assessment at 1h) 5. Biphasic pulse stimulation mode (assessment at 2h)

OTHER

Unified Dystonia Rating Scale

Neurologist use the UDRS to determine the severity and duration of dystonia on 14 body areas.

OTHER

Burke-Fahn- Marsden scale

Neurologist use the BFMDRS to rate the severity of dystonia in 9 regions of the body.

Sponsors & Collaborators

• Medtronic

  collaborator INDUSTRY

• University of Florida

  lead OTHER

Principal Investigators

• Leonardo Almeida, MD · University of Florida Center for Movement Disorders and Neurorestoration

Eligibility

Min Age

18 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2015-07-31

Primary Completion

2016-01-31

Completion

2016-08-31

Countries

• United States

Study Locations